Niagara Falls cities are twin cities that stand across the Niagara River from each other. Both cities are named after the Niagara Falls that extends between the two cities. The American city sits in Niagara County, New York while its Canadian counterpart is located in Ontario.

The falls between the two cities are the most powerful waterfalls in North America. Although not exceptionally tall, the falls are renowned for their expanse. It is estimated that during high flow, up to six million cubic feet of water falls every minute. The falls is one of the US's top 10 tourist destinations.

The falls are utilized not only for their value in tourism, but also for being a valuable source of hydroelectric power. Both Niagara Falls cities rely heavily on profits earned from tourism and from the hydroelectric power extracted from the falls. Power costs are low in Niagara because of hydroelectric power. For this reason, the Niagara Falls cities, especially the Canadian part, is home to electric based industries.

The falls has also been the setting of many movies and television shows including the 1953 American movie 'Niagara' as well as the 1980 movie Superman II. Throughout history, the falls has also fascinated daredevil performers including the tightrope walker 'Blondin' who crossed the falls in 1859.